[@Archmage MC]
A Black hole would contain him. However, as long as he's not completely destroyed, he'll eventually rebuild himself. And then he'll become immune to the black hole. Of course, it would probably take a few billion years.

Two grams of antimatter would generate 89875517873.681764x4 J of energy, or about 0.084 kilotons. That's less than 1% of the Little Boy bomb dropped on Hiroshima.

Antimatter converts both itself and the matter it touches. Else it would violate the 2nd law of thermodynamics.

Also, making antimatter is easy. The problem is storing it. How do you store something that instantly annihilates itself whenever it touches anything made of matter?